3rd gear synchro is bad

engine rebuild, will require all new gaskets, rebuild depends how far u wanna go, if u wanna do the whole thing, your gonna need to hone the cylinders at a machine shop, get new bearings, fresh rings for your pistons, if u'r autoXing the car then u might wanna go with a higher compression piston for quicker acceleration. Also, port & polish the head up so that you can flow air a little better & get all new seals & have your valves cleaned at the machine shop, you will have a little bit of a noticeable difference in the power area while accelerating out of those turns & it will run all fresh!